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The complex construction of the joint apparatus of the cat distal forelimb, which allows the paw three degrees of freedom, poses special requirements on the neural signals controlling the paw position. To understand the electromyography (emg) signals of the distal forelimb muscles during locomotion, it is necessary to know the kinematics of the forelimb joints in detail. As no such information is available, we used the pulsed X-ray technique in trained cats during treadmill locomotion to analyse the angular excursions of the wrist, the metacarpophalangeal (MCP) and the proximal interphalangeal (PIP) joints. X-ray illuminations were done in either the parasagittal or the frontal plane. At the beginning of the stance phase the wrist (WR) and the MCP joints extended slowly, and the PIP joints flexed. Whereas the WR and the PIP joints maintained a constant angular position of approximately 200 degrees and 60 degrees, respectively, throughout the stance phase, extension continued in the MCP joints from 240 degrees at touch-down to 300 degrees at the end of the stance phase. Slightly before lift-off (100 ms) the WR and the MCP joints flexed rapidly. This flexion changed approximately 150 ms after lift-off into a slow extension. The PIP joints extended rapidly at the beginning and at the end of the swing phase, during the interposed period of the swing phase they displayed a slow flexion. Rotatory movements of the forelimb in the radioulnar joints were present during the swing and stance phases. During the swing phase the limb first supinated (starting 100 ms after lift-off); pronation occurred immediately before ground contact. During the stance phase the supination angle was kept constant until 100 ms before lift-off, when a short pronation was found. The paw was kept in an ulnar deviated position throughout the complete step cycle. Ulnar deviation decreased at the end of the swing and stance phases. The results of this study increase our understanding of how the body weight is transmitted on to the ground. They suggest four main functions for the skeletomotor apparatus and the underlying neural commands to secure the forward movement of the animal during the stance phase: (i) preparation and stabilization of a force-transmitting platform; (ii) stabilization of the wrist and the carpal/metacarpal joints; (iii) stabilization of the supination angle; (iv) antigravity control of the extension in the MCP.  相似文献   
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Zusammenfassung AFP von über 500 Fruchtwasserproben aus der 11. bis 32. SSW wurde mittels isoelektrischer Fokussierung und anschlie?endem Immunoblot untersucht. Die praktische Relevanz dieser qualitativen AFP-Bestimmung bei Frühschwangerschaften wird noch weiter geprüft. Ab der 15. SSW erlaubt unser Verfahren die sichere Unterscheidung normaler Schwangerschaften von solchen mit offenem Neuralrohrdefekt bzw. intrauterinem Fruchttod.  相似文献   
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A genetic contribution to a broad range of epilepsies has been postulated, and particularly copy number variations (CNVs) have emerged as significant genetic risk factors. However, the role of CNVs in patients with epilepsies with complex phenotypes is not known. Therefore, we investigated the role of CNVs in patients with unclassified epilepsies and complex phenotypes. A total of 222 patients from three European countries, including patients with structural lesions on magnetic resonance imaging (MRI), dysmorphic features, and multiple congenital anomalies, were clinically evaluated and screened for CNVs. MRI findings including acquired or developmental lesions and patient characteristics were subdivided and analyzed in subgroups. MRI data were available for 88.3% of patients, of whom 41.6% had abnormal MRI findings. Eighty-eight rare CNVs were discovered in 71 out of 222 patients (31.9%). Segregation of all identified variants could be assessed in 42 patients, 11 of which were de novo. The frequency of all structural variants and de novo variants was not statistically different between patients with or without MRI abnormalities or MRI subcategories. Patients with dysmorphic features were more likely to carry a rare CNV. Genome-wide screening methods for rare CNVs may provide clues for the genetic etiology in patients with a broader range of epilepsies than previously anticipated, including in patients with various brain anomalies detectable by MRI. Performing genome-wide screens for rare CNVs can be a valuable contribution to the routine diagnostic workup in patients with a broad range of childhood epilepsies.  相似文献   
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Pain sensitivity is characterized by interindividual variability, determined by factors including genetic variation of nociceptive receptors and pathways. The sigma-1 receptor (SIGMAR1) is involved in pain modulation especially under pre-sensitized conditions. However, the contribution of SIGMAR1 genetic variants to pain generation and sensitivity is unknown yet. This study aimed to identify effects of 5 SIGMAR1 variants on the somatosensory phenotype of neuropathic pain patients (n?=?228) characterized by standardized quantitative sensory testing. Principal component analysis revealed that the SIGMAR1 variants ?297G>T (rs10814130) and 5A>C (rs1800866) significantly lowered thermal detection and heat/pressure nociception in particular in neuropathic pain patients with mainly preserved somatosensory function. Compared to wild-type, the variant allele ?297T was associated with loss of warm detection (P?=?.049), lower heat-pain sensitivity (P?=?.027) and wind-up ratio (P?=?.023) as well as increased paradoxical heat sensation (P?=?.020). Likewise for 5A>C the strongest genotype-associated differences observed were reduced peripheral (less heat hyperalgesia; P?=?.026) and central sensitization (lower mechanical pain sensitivity; P?=?.026) in variant compared to wild-type carriers. This study indicates lack of association of SIGMAR1 ?297G>T and 5A>C genetic variants to susceptibility to develop chronic pain, but significant modulation of somatosensory function in neuropathic pain patients.

Perspective

This article presents the first study indicating a modulation of somatosensory function in neuropathic pain patients by selected genetic variants in SIGMAR1. As our findings could contribute to the explanation of interindividual differences in drug response they might help to improve the treatment of neuropathic pain.  相似文献   
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We present clinical and developmental data on a patient with a de novo terminal deletion of the long arm of chromosome 4. Cytogenetic studies after G-banding revealed the karyotype 46,XY,del(4)(q34). The 4-year-old male showed mild facial dysmorphism, moderate mental retardation with speech retardation, and marked deficits in gross motor skills. Our patient is the second with this deletion described in the literature. In both patients the phenotype was characterized by mild to moderate mental retardation, abnormalities of the pinnae, and nonspecific facial dysmorphism. The mild phenotype might explain why only two patients with this deletion have been described so far.  相似文献   
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Reasonable formalized methods to estimate the frequencies of DNA profiles generated from lineage markers have been proposed in the past years and were discussed in the forensic community. Recently, collections of population data on the frequencies of variations in Y chromosomal STR profiles have reached a new quality with the establishment of the comprehensive neatly quality-controlled reference database YHRD. Grounded on such unrivalled empirical material from hundreds of populations studies the core assumption of the Haplotype Frequency Surveying Method originally described 10 years ago can be tested and improved. Here we provide new approaches to calculate the parameters used in the frequency surveying method: a maximum likelihood estimation of the regression parameters (r(1), r(2), s(1) and s(2)) and a revised Frequency Surveying framework with variable binning and a database preprocessing to take the population sub-structure into account. We found good estimates for 11 metapopulations using both approaches and demonstrate that the statistical basis of the method is well supported and independent of the population under study. The results of the estimation process are reliable and robust if the underlying datasets are large and representative and show small average and pairwise genetic distances.  相似文献   
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